1. Field of the Invention
The present invention relates to an air conditioning device for a vehicle which comprises a regenerative section and a battery device.
2. Description of the Related Art
In general, in a vehicle comprising an engine as a power source and an interior air conditioning device, the compressor of the air conditioning device is driven by the engine.
On the other hand, among vehicles having an engine as a power source, a type of vehicle is known in which a control generally known as an idling stop control, in which fuel supply is stopped so as to stop the engine under predetermined conditions such as when the vehicle stops, is executed.
In the case of a conventional vehicle which has an air conditioning device, and in which an idling stop control is executed, an air conditioning operation may not be performed when idling is stopped because the compressor of the air conditioning device cannot be operated.
Another type of vehicle is also known in which an air conditioning operation can be performed even when the engine is stopped. For example, in a vehicle disclosed in Japanese Unexamined Patent Application, First Publication No. 2000-179374, or in a vehicle disclosed in Japanese Unexamined Patent Application, First Publication No. 2002-47964, a compressor is adapted to be selectively driven by an engine and a motor, the engine and the compressor are adapted to be connected or disconnected by engagement or disengagement of a clutch, the clutch is engaged and the compressor is driven solely by the engine or by the engine and motor when the engine runs, and the clutch is disengaged and the compressor is driven solely by the motor.
Another type of vehicle is also known, which comprises a regenerative section for recovering kinetic energy of the vehicle during deceleration as electrical energy, and a battery section for storing electrical energy recovered by the regenerative section, and in which electrical apparatuses such as a motor for a compressor are operated using the electrical energy stored in the battery section.
The above-mentioned vehicle disclosed in Japanese Unexamined Patent Application, First Publication No. 2000-179374 is an example of such type of vehicle, which is a so-called hybrid vehicle, and in which the motor for the compressor is adapted to selectively act as the regenerative section, and as a motor for driving the vehicle as well. In this case, recovery of energy is performed in such a manner that the clutch is engaged so that the kinetic energy of driving wheels is transmitted to the motor, as a regenerative section, via the engine.
In such a vehicle, the compressor is adapted to be selectively driven by the engine and the motor, and the engine and the compressor are adapted to be connected or disconnected by engagement or disengagement of the clutch in order to perform air conditioning even when the engine is stopped; however, because the kinetic energy of the vehicle during deceleration is recovered by the regenerative section with the engine intervening, the clutch must be engaged during a regenerative operation; therefore, the compressor is inevitably driven regardless of the need for air conditioning.
In this case, a problem is encountered in that regenerated energy is reduced due to increase in friction when the compressor is driven during a regenerative operation.